Your property questions answered.

Why do councils levy charges on house extensions?

What is the story with local authorities levying charges on extensions? We are embarking on an extension to our house and have heard horror stories from friends who built an extension and then got bills from the local authority. These bills were not in relation to the supply of water or anything, simply on the basis of their extension.

I note from your address that you live in the Dún Laoghaire Rathdown County Council catchment area, though really no matter where you live in the country you'd be receiving the same type bills. People who extend their homes beyond 40sq m (430sq ft) are required to pay a development levy - the first 40sq m (430sq ft) are exempt from the charge. As developments of this size require planning permission, payment of the levy is made a condition of the granting of that permission. You are supposed to pay the charge before starting work though a staggered method of payment can generally be worked out. In other words, your friends shouldn't have been in the least bit surprised to receive a bill - it would have been explicitly stated in the conditions of their planning.

However, people often don't look at the conditions - leaving the business of the small print to their architect or builder. Your local authority charges €113.35 per sq m (€10.53 per sq ft) over the 40sq m (430sq ft) threshold. When the charge first came in in 2004, the cost was €100 per sq m (€9.29 per sq ft). It could be that your friend's planning permission was granted in 2004 but they didn't get around to building until 2006. In which case their bill would have increased and they simply didn't factor that extra cost in. It's a lesson for home-improvers to really look at the conditions of their planning and to build in the cost of the development levy into their budgets.

How can I find out how much my house is worth?

How can I find out the price a house close to mine was sold for? It was private treaty and the agent when I called would only say that it "achieved in excess of the asking price". I want to get an idea what my house is worth.

Private treaty sales are just that, private. On the auction results page of this supplement you will also see some private treaty results. Some are "over" and some are specific. It depends on whether the agent releases the information or not, and many homeowners decide to go private treaty simply because they want to keep their business to themselves and would be furious with an agent for releasing the ultimate sales price. In country areas it's not unusual for price to be available "on application" so keen are the sellers to restrict the information about price being made available. The agent in your case has declined to provide the information - though they generally can be pinned down to a ballpark figure. So barring asking the house's former owner or indeed the new owner straight out, that really is that. In any case, a neighbour's house is not an absolute guide to what your house is worth for a whole variety of reasons. It could be extended, redecorated, rewired or have a bigger garden.

Any agent will give you a valuation for your house - for a fee - but it's pretty much irrelevant unless you're thinking of selling or remortgaging.

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Unfortunately, it is not possible to respond to all questions. The above is a representative sample of queries received. This column is a readers' service and is not intended to replace professional advice. No individual correspondence will be entered into.